Track ball



FIG. 1 is a front, top, right side perspective view of a track ballshowing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is an inverted rear elevational view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof;

FIG. 6 is a left side elevational view thereof; and,

FIG. 7 is a right side elevational view thereof.

The ornamental design for a track ball, as shown and described.